Automatically-operating variable-time-exposure photoprinting-cabinet.



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J. F. WARE. AUTOMATICALLY OPEBATINQ VARIABLE TIME EXPOSURE PHOTOPBINTIHGCABINET. APPLICATION FILED 1A3. 29, 1909.

J m 8 a 9 G r 4 N W A J w W A J. P. WARE. AUTOMATICALLY OPERATINGVARIABLE TIME EXPOSURE PEOTOPBIN TING CABINET.

A PPLIOLTIOI FILED IAB. 29, 1909. Patented Aug. 9,

3 SHEETS-SHEET 2.

av if .9:

J. P. WARE.

AUTOMATICALLY OPERATING VARIABLE TIME EXPOSURE PHOTOPBINTING CABINET.

. To all 'it may concerns provement' over a James F. Ware and the frame,

, \"UNITED' STATES PATENT OFFICE.

JAMES E. WARE, or DENVER, COLORADO, assrenon. or ONE-HALF '10 ARNOLD A.-

- A BOWI-IAY, or DENVER, concnano.

AUTOMATIGALLY-OPERATING VARIABLE-TIME-EXPOSURE PHOTOPRINTING-CABINET.

Be it known that I, JAMES F. WARE, a citizen of the United States ofAmerica, residing in the city and county of Denver and State ofColorado, have invented a new and useful Automatically-OperatingVariable- Time Exposure Photoprinting Cabinet, of

which the following is a specification.

This invention relates to automatically operating, printing cabinets,and is designed as an imdevice. of this character Patent were granted toThomas W. Bundle, No. 899,235, dated September 22, 1908.

Theobject of the present invention is to rovide a suitable cabinet,having a printing rame and a padded two-part print-holding shutter,which is hinged to one end of the frame and which, when pressed downupon is held by a latch, automatically operating mechanism beingconnected with the latch, whereby the same is tripped at a predeterminedtime to release the shutter, means being employed for varying the timeduring which. the latch is caused to engage and hold said shutter. Y

A further object of the invention is to provide in combination with aphoto-print- 1ng cabinet, having a printing frame and for which Lettershinged padded print-holding shutter thereagainst the frame for a for,mechanism for holding said shutter predetermined time, said mechanismcomprising a liquid-controlled,.gravity valve, and mechanism operated bysaid valve and connected with a latch for lockin the shutter, wherebywhen the shutter is c osed against the frame, the

said latch is operated to engage the shutter and hold the same untiltripped by the mechanism, which is operated by the valve on itsdescent,- the valve being normally held in an elevated position Afurther object .of the invention is to rovide a cabinet of thischaracter having a ight chamber at one end thereof, communicating withthe cabinet, said chamber being normally closed by a door of suitablycolored fabric, which is opened and closed automatically throughconnection with the valve controlled mechanism, so as to admit light tothe cabinet when printing and shut it out when'the shutter is released.

, These objects-are accomplished by the Specification of Letters Patent.Application filed March 29,1909. Serial No.

- and latched.

vlongitudinal'sectional view of the cabinet,

variable time, exposure. photo cabinet and light chamber 0 n. Y of theand Fig. 9, is a the numeral 1,

by said mechanism.

mechanism illustrated drawings, in which:

Figure 1, is a plan view of the improved cabinet, showing the shutterpressed down F 2, is a central, vertical the print-holding Patented Aug.9, 1910.

in the accompanying shntter being open, and

the operating mechamsm being in its normal or inoperative position. viewof the cabinet, the front door of the same being open, showing theshutter down, the mechanism set, the valve stem in the act ofdescending, and the shutter between the Fig. 4, is a vertical sectionalview operating valve. Fig. 5, is a horizontal sectional view thereof, onthe line 55 of Fig. 4. Fig. 6,

F ig. 3,-is a front is a front view ofthe valve tube, showing 7 thetriangular port therein. Fig. 7, is a ont view of the cut-off valvewhich fits in the tube. Fig. 8, is a fragmental, horizontal sectionalview, on the line 88 of Fig. 3, showingithe operating mechanism in plan,plan view of a bracket which supports a portion of the operating mechan-1SII1. I

Similar' characters of reference refer to similar parts throughout theseveral views.- Referring to the accompanying drawings,

indicates a rectangular casmgor cabinet, which is supported upon legs 2,and which is provided at its forward end 7 with a door 3, which givesaccess to the interior of the cabinet. Anopening 4, of suitabledimensions, is formed in the rear end of the cabinet, whichcommunicates with a semi-circular casin 5, which is secured upon thisend of the cabinet, and this end is preferably hinged to the cabinet, asshown bydotted lines, Fig. 1. The casing 5, is preferably a metalliccasing, and its upper end has an opening 6, which permits a suitableilluminating withdrawn from, the casing, and which also permitstheescape of heat generated by said illuminating means.

the cabinet, is a strip 7 of felt, and a door 8,

Around the opening 4, on the inside of means to be placed in, and' isadapted to normally close the opening.

This door or shutter comprises a frame, which is secured at its lowerend upon a horizontal rod 9, pivoted at each end in bearin s 10, andwhich is referably covered by a s eet' of suitably col ored fabric. OneI which .is attached at its opposite end to the adjacent end of thecabinet, and normally keeps the door closed. The opposite end of the rodis also bent'at an angle, and is pivotally comiected to one end of aConnecting rod 11, the opposite end of which is pivotally attached to anarm 12, which is rigidly separt of a bracket 15, securedto the topvof"their adjoining edges, withv aperturedflugs cured upon a shaft 13,which extends partially across the cabinet adjacent to its forward end,and through one side of the same,

the projecting end of the shaft being provided with a handle 14. Thisshaft is journaled in bearings which form an integral the cabinet. Thebracket is provided centrally with a depending plate 16,- having guidelugs 17 arranged in pairs at its opposite extremities, and a pairof'bearing lugs 18, at a point between the guide lugs, which support theinner end of the shaft 13, while the shaft is ful'ther su'pported by abearing 19, which is formed on a depending arm at the end of the bracketadjacent to that end of the shaft having the handle14. A gear wheel 20,is rigidly mounted on the shaft, between the bearing lugs 18, and thiswheel meshes with a rack bar 21,, which lies between the guide lu gs 17.The upper end of this rack bar is normally flush with the top of thebracket 15, and its lower end extends a suitable distance below thelower end of the plate 16, and'terminates in an arm 22, which extends atright angles to the bar, and is bifurcated at its outer end;

An arm 23, extends at right angles from near the inner .end of the shaft13, and nor; mally maintains an approximately horizontal position, and asimilar arm 24, extends at right angles from about the central portionof the shaft, and this arm normallymaintains a position approximatelymidway between a horizontal and a vertical plane.

The arm 24, is adapted to be engaged by a latch 25, when the mechanismis set, as in Fig. 3,'and this latch is pivotally suspended from asuitable bearing 26, secured t6 the top of the cabinet. The arm 23, isadapted to engage the horizontal portion of a depending arm27, which issecured to a horizontally disposed member of a bell crank latch 28,which is pivotally mounted in a bracket 29, secured to the to of thecabinet. The latch member of this be 1 crank, extends up through a slot30,- in the top of the cabinet, and is adapted to engage and hold aprint holding shutter 31, whichis hinged to the rear end ofa cushionedprinting frame 32, when said shutter is pressed down upon said frame.plates 33 and 34, which are provided upon 35 and 36 respectively,through which passes a 'rod;37,- which connects the two-plates inuniform throughout.

' springs The shutter comprises two the springs, v or cushion supportsfor the forward end of hinged relation. This rod is encircled by theoppositely coiled portions of a spring 38, the ends of which are securedin apertures in the lugs 36, while the connecting portion of the twocoils is formed into a loop 39, which is secured to the forward plate33, by a screw 40. The tension exerted by the spring 38, is suflicientto normally hold the plate 33, at an angle to the plate 34, and thisangle is defined by a stop lug 41, on one'of the lugs 35, which engagesthe adjoining lug 36.

The printing frame is rectangular in form, and lies in a correspondinglyshaped opening in the top of the cabinet, and is hinged at its rear endto the top of. the cabinet, as shown. Upon the rear end of the frame, issecured a metal plate 42, having a pair of apertured lugs 43, adjacentto each end. An eye bolt-44, is placed between each pair of lugs and arod 45 is passed through the lugs and bolts. The plate 34 of the printholding shutter is provided atv its rear end with lugs 46,havingvertical apertures through which the eye bolts 44 pass. Coilsprings 47 encircle the bolts and rest upon the' lugs 46, and thesesprings are held under tension by nuts, which are screwed upon the endsof the bolts. loil springs 48 encircle the rod 45, and the forward endof each spring issecured in an apertured lug 49, near the front edge ofthe plate, while the opposite ends of the springs engage the plate 42.The

tension exerted by the springs 48, normally holds the shutter up andaway from the frame, and when the shutter is pressed down upon a glassplate 50, which is supported in the frame flush with its upper face, andupon which the photographic negatives and sensitized paper are placed,its member 34 will first contact with the glass plate, and the memberwill contact immediately afterward. I

The under sides of the shutter members are, provided with feet pads 51,which insure an even pressure'upon the plate 50, and the springs 47"permit the shutter to adjust itself to the thickness of the materialbeneath it, so that the pressure on the said material is Theforward endof the'frame 32,- is normally held at slight elevation above the top ofthe cabinet by headed rods 52, which pass through vertical the saidframe,

the object of which will appear later.

120.- posed between the heads of the rods and at its upper en the glassplate 50, the ro is pushed A socketed lug 57, is formed on the for ward'end'of the shutter plate 33, through which passes a usher rod 58,having a knob d. A pin 59 passes through the rod, within the socket, anda spring 60 is interposed between the said pin andv the bottom of thesocket, which normally holds the pin up against a cap disk 61, which issecured in the top of the socket by set screws. 1

When the shutter 31, is ressed down upon 30, and engages the top ofthe-rack 21, which down thereby turning the gear wheel 20,.and with itthe the arms 23 and 24, which are given a par- -tial revolution. The arm24, is engaged by the latch 25, while the arm 23 is moved an equaldistance 'at the same time, and releases the arm 27, which is thenlifted by a spring 62, thereby rocking the bell crank latch 28, passesthrough an opening 63, in the shutter plate 33, when the plate isdepressed, and enga es the rear edge of the said open-' ing, there yholding the shutter down until the latch 28 is rocked to releaseltheshutter,

which operation is accomplished in the 'following manner:' To theforward portion of the floor of the cabinet and centrally of its width,is securedan oil controlled valve 64,

comprising a main vertical cylinder 65, and a branch cylinder 66, whichcommunicates with the main cylinder near the opposite endsof the same. Abase plate 67, forms a of the cylinder and bolted to the floor of thecabinet. A c.(p

' through the bifurcated end closure for the lower end of'themain cylinder, and'this plate is screwed upon the end 68, having a centralaperture, is screwe upon the upper end 'of the main cylinder. A piston69, provided 'with suitable packing rings, is located in the maincylinder,'and a rod 70 is secured to the piston and extends through thecap 68, and up ofthe arm 22, at the lower end of the rack bar 21. Across arm 71 passes through the rod 70, and this arm normally rests uponthe bifurcated end of the arm 22, and the piston is thereby maintainedin an elevated osition. Vertical rods-71 at the end of the ifurcated arm22, engage the cross arm 71 and prevent the rod 70 from wisting. An arm72 projects from the ,upper end of the rod, 70, and when therod'descends,'this arm 72 isadapted to engage an arm 73, whichfrojectsfrom 'the atch 25-into the ath o the .said arm 72, whereby thesaid atch is tripped and the arm'24 released, permitting the shaft13'and gear 20 to be partiall rotated by the spring 10, through the meium of the rod 9, connecting rod '11, and arm 12. A spring 74 7connected at one end to the arm. 73, and at the other to the top of thecabinet, normally holds the latch 25 in position to be engaged 58 entersthe slot shaft 13, carrying of the said piston.

portion of the latch, the latch is immediately arm 24, by a suitablestop at its upper end.

arm. The latch is limited in its g The piston 69 is provided witha-vertical aperture or port 75, which extends through it from top tobottom, and a disk valve 76 covers the lower endof the port. This diskvalvehas a stem 77, which extends down through a guide sleeve 78projecting from the step portion'of a bracket 79, which is secured tothe bottom of the piston. A coil spring 80 encircles the valve stem andsleeve, and is interposed between the disk valve and the step. A pin 81,inthe base plate, limits the downward movement of the piston, and a pin82 in the upper end of the piston is designed-to contact with thecylinder cap, and define the upward movement A valve tube 83, is sweatedor otherwise rigidly secured in the upper end of the branch cylinder 66,and this tube is providedwith a narrow triangular port 84, which facesthe passage connecting the main and branch cylinders at their upperends. A cut-off valve 85, is snugly but rotatably mounted in the tube83, and an annular shoulder 86, is formed on this valve, which restsupon the end of the valve tube 83, and limits the downward movement ofthe cut-off valve within the tube. The lower portion of the cut-off istubular and open to the branch cylinder, and a port -87, i's formed inthe said tubular portionof the cut-off, which. to register with the port84 of the valve is designed tube. A stem 88 is secured to thecut-ofi'and this stem extends up through the top of the cabinet securedupon the endof the stem and is provided with a knob 01; handle bywhich-the pointer may be turned to any one of the graduations on theplate, which are numbered from 1 to.15,andindicate a correspondingnumber of seconds. The valve is and through the axis of a graduated,semi-circular plate 89, and a pointer 90 is filled with oil, as shown inFig. 4, and when the piston is raised, the oil is forced through itsport- 75, and the instant the piston ceases to'move' upward, the diskvalve 76 is thrown by its spring 80,-to close the port 75, and

when the piston is permitted to descend it forces the oil up through thebranch cylinder and cut-off, whence itpasses through the ports 87 and 84of the cut-ofl and valve tube respectively, and into the upper end ofthe main cylinder valve. The time occupied by the descent of the pistonis governed by the position of the cut-off-port 87, relatively to theport 84. T'Vhen the two ports exactly register, the piston drops in theshortest period of time indicated on the graduated plate, and as thecut-ofl' is turned so that the rear edge of its port 87, approachesnearer and nearer tosthe narrow end of the triangular port 84, the areaof the exit.

responding ratio. A vent tube 91, is screwed in .the upper end ofthevalv'e where the main cylinder and branch cylinder communicate.

In the practical operation of the device,

I the casing or chamber is provided with a necting rodll, which opensthe door 8, and

suitable lighting medium, such as an electric or acetylene lamp, andbefore actual printing is commenced, experimental tests are made toascertain the light power, and the probable length of exposure requiredfor the character of workin hand, and this is accomplished by placingthe negative on the glass plate of the printing-frame, and operating thehandle 14,-which turns the shaft 13, and gear wheel 20, which causes thearm 24 to engage the latch 25, and lowers the rack bar 21, with its arm22, which supports the cross arm 71 and holds the rod 10 and piston 69in an elevated position. At the same time the arm 12, draws upon theconpermits the light from the chamber ,5 to shine into the cabinet, andupon the nega tive, the tone of which determines the prob: able lengthof exposure necessary for the best results. Meanwhile, the pistondescends, until the arm 72 engages the arm 73, by which the latch 25 istripped, and the parts of the mechanism and thepiston are restoredtotheir normal position, and the door. 8, is ,closed to shut dut the lightfrom the cabinet, this being accomplished by the spring 1,0 acting uponthe hinge rod 9, connecting rod 11 and arm 12. In this test worktheprint holding shutter 31 is left open so that the operator may lookthrough the glass plate 50, but when the probable length of time hasbeen ascertained, and the pointer 90 set accordingly, the negative ornegatives with the sensitized paper" are placed upon the glass plate50,- and the shutter 31 is pressed down upon them, in doing this theoperation above mentioned is repeated, engagement with the. rack tatesthe gear wheel of the end of the pusher rod 58,

bar 21,v which partially ro- 20 and shaft 21, looking and only it is noweffected by thethe arm 24 tothe latch 25, and lifting. the

arm 23 from the arm 27, which is immediately lifted by the spring 62,whereby the -latch28 is rocked to engage the plate 33 of the printholder, but not until after the said latch has passed through the.opening 63 in'the said plate. The door 8, opens in the mannerabovestated, andstands at such an angle as to throw" the light. from thechamber 5 directly up against the glass 'as above described, and arm 23engages arm 27, which rocks the latch 28 an d reof the door as it opensand closes.

plate 50, and at the expiration of the time indicated by the pointer 90,the piston reaches the limit of its downward move. ment, the latch 25 istripped by the arm 72,

leases the print holder. y

' When the print holder or shutter is pressed down, it also depressesthe forward end of the printing frame 32, upon the is under tension, itinsures perfect contact of the same with the print holder, andconsequently of the negatives with the sensitized paper; and as the saidshutter is released and flies up under the action of its springs 38' and48, the frame 32 under the upward pressure of its springs 54 will followit, thus keeping the negatives and sensitized paper firmly pressedtogether-until after the light has been cut oif by the closing of thedoor 8. The spring 55, modifies-the action of the springs 54 upon .thecushioning rods 52, and

when the shutter 31 is thrownyopen by the action of its springs 38 and48, itis retarded in its upward movement, and brought gradually to astop, by

pivoted at one end'to a post 93, secured to the top of the cabinet,while its piston rod 94 is pivotally attached to a bifurcated lug 95,near the forward end of the shutter plate 34. A strip 96, havingslidewaygrooves, is. secured upon each side of the bottom of the printing frame32, in which the vignetting sheets are slipped and supported, and theframe may be lifted for this purpose by a knob 97. A segmental arm 98 isalso secured adjacent to one side ofthe door 8,, and this arm isprovided with a segmental slot 99,

serves to steady the movement Thesaid door being covered with fabric, islight and. easily operated, and the felt strip. 7, surrounding theopening 4, not only serves to exclude the light when the door is closed,but alsoicushions the impact of the door and 8, travels, and

deadens the sound which would otherwise be caused thereby. 1

The device herein described, provides for accurate, variable, timeexposure printing from photo-negatives and the like, and insures auniform exposure for any desired number of prints for any desired periodof time for which the operating valve 15 set.

Having described the invention, what I claim as new and vdesire tosecure by Letters, Patent, is:

1. In a photo-printing machine as speci-' fied, the cfmbination with a.cabinet; a

printing frame in the top of the cabinet, and

hingedat its rear end to said cabinet; resili- J .ent supports for thefront end of-said frame,

anda two-part print holding shutter. hinged 130 cushioning rods 52, andas the said frame means'of an ordinary pneumatic cush omng cyllnder 92,whlch 1s in which a guide pin 100, secured to the door said frame; of as ring operated latch for said shutter; a sha an arm carried by saidshaft which normally holds said latch in an inoperative -position; meansfor turning the shaft when the shutter is closed, whereby the said armreleases the latch, which immediately engages and holds the shutter; asecond arm on said shaft; a latch in the path of said arm, which engagesthe same when the shaft is turned; an automatically operating gravitydevice for tripping said second latch at a predetermined time; a springshaft, whereby the shutter release the shutter; shutter up;

to the rear end of latch is moved to springs for throwing the and meansfor cushioning its movement.

' inoperative position; a

when

2. In a photo-printing machine as speci-.

fied,'the combination with a cabinet having a hinged rinting framejn itstop; and a print hol er hinged to said frame; of a spring-operated latchadapted to engage the forward end of said print holder; a shaft;

2. gear wheel on the shaft; a rack bar in mesh holder is released; andsprings for throwing up the said holder.

3. In a photo-printing machine as specified, the combination witlracabinet, having a hinged rinting frame in its top, and a print hol erhinged to said frame; of a spring operated latch adapted to engage saidshutter is print holder; means for normally holding said latch in aninoperative position; means operated by'the print for releasing saidholding means, whereby the latch engages the print holder, and foroperating said holding means for moving said latch at a predeterminedtime to f elease the print holder; and means for throwing the 1printholder up, when released from the .late i 4. In a photo-printing machineas specified, the combination with a cabinet having at its top a hingedprinting frame, resili- 'ently supported at its free end; a printholdsprin'gs for normally holding said shutter .up; of a spring-operatedlatch-for said shutter' a sh aft; :1 gear wheel on the shaft; a melt barin engagement with the gear wheel; a hand-operated pusher rod on saidshutter which depresses said rack bar, when" the closed, and partiallyrotates the said piston rod elevated; an arm carried by said forreversing the files bac println holder when closed,

silient supports beneath the front end of the frame, and

mmed tune;

. with the latching of the for the shaft; an arm carried by the shaft,which normally holds the latch in an inoperative position but releasesthe same to engage the shutter when the shaft is turned; asecond armcarried by the shaft; a sprin controlled latch in the path of said seconarm; a gravity valve having a piston rod; an arm carried by the rack barfor normally holding piston rod for tripping said last mentioned latch,when said rod descends; a spring for restorin the shaft to its normalposition whereby the shutter is released and it; and means for retardingor accelcrating the movement of the piston rod.

5 In a photo-printing machine as specified, the combination'wi'th' acabinet, of a frame in an opening in the topof said ca inet, and hingedat its rear end to said cabinet; resilient supports for the front end ofsaid printing frame, which normally hold said frame at an inclination toa horizontal plane; a two-part padded shutter hinged upon the rear endof said frame; springs for normally holding the shutter open; a springoperated latch for engagingshutter when closed; and means for ansaidtomatically tripping said latch to release the v shutter at apredetermined time. I

6. In a photoprinting machine as specified, the combination withacabinet, ofa printing frame hinged at its rear end in'an opening thetop of said'cabinet; springsupported rods beneath the forward end of saiprinting frame, which normally elevate 1 said forward end; aprint-holding shutter hinged to the rear end of said frame; springs fornormally holding said shutter open; a s ring operated latch for engagingsaid shutter when closed; and means for automatically tripping saidlatch to release the Shutter at a predetermined time.

7. In a photo-printing machine as specifi a cabinet; a light receivingchamber on the rear end of said cabinet; a spring-operated door whichnormally closes communication between the cabinet and light chanr her; aprinting'frame hinged at. its rear end m an opening in the top of thecabinet; re

frame, which normally hold the same at an elevation; a print-holding.shutter hinged to the rear end of the frame; springs for normallyholding said shutter up and away from the frame; a spring operated latchfor holding the shutter when closed against the frame; means forautomatically tripping the latch to release the shutter at a predeterandmeans for opening the door 'of the light chamber simultaneously shutter.

8. In a device as specified, the combination with a cabinet; a hingedprinting frame in the to of the cabinet; resilient supports fdrward endof the frame; a print 130 v means for retarding or accelerating themovement of the gravity device;

9. In a device as specified, the combination with a cabinet; a hingedprinting frame in the top of the cabinet; resilient supports for theforward end of the frame; a print liolding shutter hinged to the rearend ofv the frame; a latch for holding the shutter against the frame andsprings for exerting an upward pull upon the shutter; of means fortripping the latch comprising a revoluble member; an arm carried by saidmember; means for partially revolving said member, simultaneously withthe latching of the shutter; a latch for engaging said member when thusrevolved; means for tripping the latter latch at a predetermined time;and a spring for restoring the revoluble member to 1 its normalposition, whereby the arm carried thereby trips the shutter holdinglatch;

10. In a device as specified, the combination with a cabinet; a printingframe in the top of the cabinet hinged at its rear end; resilientsupports for the front end of said frame; a print holding shutter hingedat its rear end to said frame; springs for normally holding said shutterup and awa from the frame; a spring controlled latch. or holding saidshutter against the frame;-a light receiving casingcommunicating withthe cabinet; and a spring-controlled door for normally closing saidcasing; of means for tripping the shutter latch, comprising a shaft; anarm carried by the shaft, which normally holds the shutter latchinoperative; means for turning the said'shaft to lift the arm and freethe latch simultaneously with the closing of the shutter; a second armon the shaft; a latch for engaging said second arm when the shaft isturned; a connecting rod attached to the door of the light chamber andto a crank on said shaft; a gravity valve for automatically tripping thelatter latch at a predetermined time, whereby the shaft is reversed bythe spring of the light chamher door, and the shutter latch thrown torelease the shutter; and means for accelerating or retarding themovement of the gravity valve.

11. The combination with a cabinet as specified; a printing frame in thetop of the cabinet; a print holding shutter hinged to the saidframe;springs for normally exerting an upward lifting tension on the shutter;and a spring controlled latch for em gaging the shutterwhen closed; ofmechanism for freeing the latch at a predetermined time, comprising ashaft; a gear wheel on theshaft; arack bar in mesh with the (gear wheel;a radially disposed ar'mcarrie the shaft in normal contact with theshutter. V

latch to hold it out of operative position; a manually operated push rodon the shutter for depressing the rack bar to turn the shaft and freethe shutter latch; a second arm carried by the shaft; a latch to engagesaid second arm when the shaft is turned; a gravity device for trippingthe latter latch, comprising a pair 0 communicating cylinders con-tammga suitable liquid; a piston in one of said cylinders, having a verticalport; a valve for closing the lower end of said port; a pistonrodextending up from said piston; an arm carried by the rack bar 7 forengaging said piston rod and normally holding the piston elevated, andwhich frees the piston when the rack bar is depressed; an arm at theupper end of the piston rod for tripping the said latter latch when thepiston descends; a cut-off in the opposite cylinder for regulating theflow of the circulating liquid as the valve descends; a rod connectedwith the cut-off and extending above the top of the cabinet; a graduatedplate on said cabinet; a pointer on the rod, above the graduated plate;and a spring for restor'ng the shaft to'its normal position when elatter latch is tripped.

12. In a photo-printing cabinet as specified the combination with ahinged print holding shutter; springs for normally holding said shutteropen and a spring operated latch for holding the shutter when closed; ofa releasing mechanism forthe latch, comprising a shaft; a gear wheel onthe shaft;

a rack bar in engagement with the gear wheel; an arm at the lower end ofthe rack bar; an arm on the shaft for engaging the latch; a second armon the shaft; a latch for engaging the second arm; ping the latterlatch, comprising a liquidcontrolled gravity valve having a piston andpiston rod, said rod being in position to en gage and trip the saidlatch on its descent, and being normally supported by the rack bar arm;means for retarding or accelerating the movement of the valve; means fordepressing the rack bar simultaneously with the closing of the shutter,whereby the shaft is partially rotated and held by the engagement of thelast mentioned latch with the means for tripsaid second arm of theshaft, and the piston is released; and a spring for restoring the shaftto its normal position, whereby the shutter latch is operated to releasethe shutter.

13; In a photo-printing cabinet, the combination with a spring operatedprint holding shutter; a latch for said shutter; means for trippinoperatin' said .trlpping means at a predetermine time, comprlsing 'aliquid controlled gravity valve having a piston and V and said latch; ofmeans for a piston rod in cooperative relation to said tripping means;means for normally supporting the piston and rod in an elevatedposition, and for releasin the piston simultaneously with the closing ofthe shutter; means for elevating the piston simultaneously with therelease of the said shutter; and means for retarding or for acceleratingthe movement of said piston.

14. In a photo-printing cabinet as specified, the combination with aprinting frame hinged at its rear end; of resilient supports for thefront end of said frame; parallel slide-ways on the under side of theframe; a hinged spring-operated print holding shut ter in'cooperativerelation to said frame; a latch for holding said frame when closed; andmeans for tripping the latch at a predetermined time to release theshutter.

15. The combination with a photo-printing cabinet, having a hingedprinting frame; of a print-holding shutter comprising a pair of platesunited by a hinge connection; a yielding hinge connection between therear end of the rear plate, and the rear end of said frame; springs forlifting said shutter; springs for swinging the forward plate of theshutter upon the rear plate; a latch for holding said shutter down uponthe frame; resilient supports for the front end of the frame; and meansfor releasing the latch at a predetermined time.

16. The combination with a photo-printing cabinet, having ahingedprinting frame; of a print-holding shutter comprising a pair of platesunited 'bysa hinge connection; a spring for lifting the forward platerelatively to the rear plate; apertured lugs on the rear plate; eyebolts pivotally attached to the rear end of the frame, which passthrough said apertured lugs; adjustin nuts on the ends of the bolts;springs on sai bolts interposed between said apertured lugs, and thenuts, and a sprin for raising said shutter; a latch for holding theshutter in contact with the frame; resilient sup orts for the front endof the frame; para lel slide- Ways on the under side thereof; and meansfor releasing said latch at a predetermined time.

17. In a photo-printing machine as specifled, the combination of asuitable supportreleasing the latch simultaneously with the closing ofthe shutter; means for holding .position; means for moving said arm andthe arm when the shutter is latched; and

means for automatically at a predetermined time. I

In testimony whereof I affix my signature in presenceof two witnesses.

JAMES F. WARE.

releasing the arm Witnesses:

G. SARGENT ELLIOTT, 'ADEIILA M, FOWLE.

